A battle with indestructible still loses defense counters as it's dealt damage
Enlightened Tutor may get you an enchantment or artifact for a single mana, but you lose a card (the tutor), and you still need to cast said enchantment or artifact
Graveyard commanders are a pretty broad topic: There are commanders that care about casting spells from graveyards, that let you cast spells from graveyards, reanimator commanders, discard commanders, self-mill commanders, and other ways to fill the graveyard if your strategy touches the graveyard, theres a commander for it
However, they are widely accepted for "kitchen table" casual play, playtesting decks, and Cube drafts, provided they are clearly marked as proxies and not sold as authentic cards
a while ago
When youre on the offense with The Akroan War, there are actually two cases for the second turn